Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already claim readOnly, openWorld, idempotent, and non-destructive behavior. The description adds useful behavioral detail beyond that: it returns a weighted 0-100 score, covers multiple SEO signal categories, and includes evidence and recommendations. It does not discuss rendering/credit trade-offs, but those are captured in parameter descriptions, so the gap is minor.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two sentences with no filler. The first sentence front-loads the action, and the second packs the output details and audit scope into a compact list. Every clause earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given complete parameter descriptions, rich annotations, and an output schema, the description covers the core purpose and result format well. It does not explicitly position the tool against siblings or mention single-page scope, but the phrase 'a webpage' and the sibling list keep this gap minor.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%: each parameter, including url, render, wait_until, and wait_for_selector, has a meaningful description covering format, enums, defaults, and credit implications. The tool description itself does not add parameter-level detail, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb ('Run an SEO audit') and resource ('a webpage'), and enumerates the checked dimensions (metadata, headings, images, canonical signals, robots directives, social tags, schema, content length). This clearly distinguishes it from sibling single-purpose tools like tooltrace_metadata or tooltrace_links, and it also specifies the output (score 0-100, evidence, recommendations).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description clearly implies use when a comprehensive on-page SEO evaluation with a score and recommendations is needed, as opposed to extracting individual components with sibling tools. However, it does not explicitly name alternatives or state when not to use this tool, so it stops short of a 5.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.